Coil retaining structure



United States Patent COIL RETAINING STRUCTURE Dale F. Willcox, Aurora,111., assignor to Furnas Electrio Company, 'Batavia, 11]., a corporationof Delaware Filed July 10, 1959, Ser. No. 826,233

2 Claims. (Cl. 317-158) The invention relates to magnetic switchstructure of the character including a magnetic field piece and a coilfor energizing the same, and has reference in particular to improvedretaining means for releasably and resiliently retaining the coil withinthe field piece.

An object of the invention is to provide coil retaining means of simpleand inexpensive structure and which will releasably retain a coil of thesolenoid type within rccesses provided therefor in a field piece oflaminated metal.

Another object is to provide a coil retainer in the form of a springclip which can be easily and quickly attached to the side frames of thefield piece by means of tabs integral with and bent out from the metalof the side frames.

A further object is to provide a resilient clip consisting of a lengthof spring wire having a special configuration whereby to adapt the samefor releasably and resiliently retaining a coil and a field piece inassembled relation.

With these and various other objects in View, the invention may consistof certain novel features of construction and operation, as will be morefully described and particularly pointed out in the specification,drawings and claims appended thereto.

In the drawings which illustrate an embodiment of the device and whereinlike reference characters are used to designate like parts- Figure 1 isa top plan view of a coil and field piece combination and wherein thecoil is releasably retained within the field piece by the coil retainingmeans of the invention;

Figure 2 is a front elevational view of the coil and field piececombination of Figure 1 and which clearly illustrates the clip of theinvention in retaining the coil within the field piece;

Figure 3 is a side elevational view of the coil and field piececombination and showing the retatining clip for the coil;

Figure 4 is a sectional view taken substantially along line 44 of Figure2; and

Figure 5 is a side elevational view illustrating the formation of theresilient clip prior to its attachment with the field piece.

The embodiment of the invention selected for illustration in thedrawings essentially consists of a magnetic field piece identified inits entirety by numeral 10, and a coil 12 of the solenoid type and whichis adapted to be retained within the field piece to provide theconventional coil and field piece combination. The field piece is formedof laminated metal plates 14 which are stamped or cut to theconfiguration desired and which in the illustrated embodiment generallysimulates a U, as best shown in Figure 3. It is preferred that the fieldpiece have a center tongue portion 16 which extends inwardly from thebase 18, being disposed equidistance between the legs 20 and 22. Themetal plates are assembled in stacked relation on respective sides of adividing center Patented May 2, 1961 member 24 of copper and theassemblage is faced on each side by a frame member such as 26 and 28.Rivets 30, or other fastening means, are employed to secure the partstogether, including the plates 14, the center member 24 and the framemembers 26 and 28, to form a unitary structure.

The coil 12 is approximately rectilinear in front elevation, as bestevidenced by Figure 2, although its shape is not particularly criticalto the invention. The coil is assembled with the field piece by beinglocated within recesses 32 formed by the center tongue portion 16 and bythe top and bottom legs 20 and 22 which have a length in excess of thetongue. The structure as described is substantially conventional indesign as regards magnetic switch devices of the type adapted to have amovable armature associated therewith.

For supporting the coil and field piece combination, the side framemembers 26 and 28 provide the bottom flanges 34, which are bent toextend laterally on each side of the structure. The top flanges 36 arelikewise similarly bent from the side frame members so as to projectlaterally on each side and the said top flanges may be employed forfastening other parts of the switch device to the magnetic field piece.The numerals 38 and 40 indicate the terminals of the coil 12, it beingunderstood that the windings of the coil are encased in a suitableplastic for adequately insulating the windings and for strengthening thecoil so that it can be conveniently handled as a unit.

The releasable clip 42 of the invention is best shown in Figure 5, thesame consisting of a length of spring wire which is bent into thespecial shape as shown. The resilient clip includes a relatively flatcenter portion 44, side legs 46 which are bent from the main body of theclip to form approximately a right angle therewith. The terminal ends 48of the clip extend laterally on respective sides of the same and eachterminal end has approximately a right angle relation with itsrespective leg. The resilient clip is employed for releasably andresiliently retaining the coil 12 in assembled relation within the fieldpiece 10 and for this purpose the coil on its outward exposed surface isformed with at least two sets of spaced parallel ribs indicated by thenumerals 50 and 52. It will be observed that a pair of spaced parallelribs is located on each lateral side of the coil and on that surfacewhich is exposed when the coil is operatively positioned within themagnetic field piece. The space between each set of ribs is adapted tobe occupied by the center flat portion 44 of a resilient clip. The sideframes 26 and 28 are each provided with a pair of tabs 54 and 56,respectively. The tabs are integral with their side frame member, beingcut from the metal thereof and bent outwardly so as to form a latch orthe like for receiving the terminal ends of a resilient clip. Thepositioning of the tabs 54 and 56 as regards each pair is such that theyare spaced longitudinally a distance approximately equal to the spacingof the terminal ends of a clip and also each pair of tabs have alocation on their side frame member so that when the terminal ends of aresilient clip 42 are engaged thereby, the flat center portion 44 of theclip will apply the desired resilient pressure to the plastic encasedcoil 12.

It is relatively easy to assemble and disassemble the coil from itsfield piece when using the resilient clip of the invention for retainingthe parts together. The center portion 44 of each clip is convenientlylocated within the groove provided therefor by its parallel ribs either50 or 52. The ribs thus maintain the clip in the desired position on thecoil and said ribs prevent excess movement bodily of the clip, whichmovement if allowed to take place might result in inadvertent release ofthe clip from the tabs. It can also be mentioned that the terminal ends48 of the clip can be easily and quickly latched by the tabs and just asquickly and easily unlatched. Accordingly, a simple and inexpensiveretaining means is provided for the coil and field piece combination andwhich is; so located that the said means does not interfere with theparts or elements of the switch although the same is readily accessibleto the operator should he desire to remove or replace a coil.

It is to be understood that this application is not to be limitedby theexact embodiments of the device shown, which are merely by way ofillustration andnot limitation as various and other forms of the devicewill, of course, be apparent to those skilled in the art withoutdeparting from the spirit of the invention or the scope of the claims.

'What is claimed is:

- 1. In a device of the character described, a solenoid type of coil anda field piece for assembly with the coil, said field piece consisting ofa metal body portion and which is faced on each side by a side framemember also of metal, a pair of lugs bent from the metal of each framemember and being disposed in longitudinal spaced relation on the outersurface of its member, said coil having a pair of spaced parallel ribsadjacent each lateral side of the coil and on that surface which isexposed when the coil is assembled with the field piece, and resilientclips for releasably retaining the coil and field piece in assembledrelation, each clip having a substantially fiat center portion and aterminal end at each side of the center portion and spaced from thesame, each clip when operative for retaining the coil and field piece inassembled relation having its terminal ends latched by the lugsrespectively and having its center portion in contact with the coil at alocation between the ribs at its particular side of the coil.

2. In a coil and magnetic field piece combination, retaining means forreleasablyrand resiliently retaining the coil within the field piece,said coil being encased in a lastic housing and being approximatelyrectangular with a center aperture, said field piece consisting of metallaminations and which are faced on each side with a metal side framemember, said field piece having approximately the shape of a U with acenter portion projecting inwardly from the base, whereby a recess isprovided within the field piece on each side of the center portion, a

pair of lugs bent from the metal of each frame member and being disposedin longitudinal spaced relation on the outer surface of its member andadjacent the top and bottom of the said magnetic field piecerespectively, said coil at each side of the center aperture havingformed integral therewith a pair of spaced, parallel ribs andwhichproject from the surface of the coil that is exposed when the the coilis operatively assembled with the magnetic field piece, and saidretaining means comprising resilient clips, each clip having asubstantially flat center portion and a terminal end at each side of thecenter portion and spaced from the same, each clip when operative forretaining the coil and field piece in assembled relation with the coiloccupying the recesses thereof having its terminal ends latched by thelugs, respectively, and having its flat center portion in contact withthe coil at a location between the ribs at its particular side of thecenter aperture. 1

References Cited in the file of this patent UNITED STATES PATENTS2,094,119 ,Werner Sept. 28, 1937 7 2,130,653 Russell Sept. 20, 19382,546,000 Immel Mar. 20, 1951 2,550,110 Ellis Apr. 24, 1951

